Our story
About Clarks Size Calculator
One job, done well: turn the 2 numbers on a Clarks Foot Gauge into a Clarks shoe size and width fitting, on any phone, in any of 18 languages.
- 2gauge numbers in, one size out
- 18languages
- 14fitting guides
- 0sign-ups or tracking cookies
What you'll find here
The size calculator
Enter the length (97 to 281) and width (67 to 227) from the gauge. You get a shoe size and a width fitting. Open the calculator
The Clarks size chart
UK, EU and US sizes for kids, women and men, with foot length in cm, mm and inches. See the chart
Fitting guides
How to use a foot gauge, width fittings, school shoes, first shoes and more. Read the guides
18 languages
Families around the world can use the calculator in the language they read best. Pick a language
What Clarks Size Calculator is
Clarks Size Calculator is a free website that reads the 2 numbers from a Clarks Foot Gauge and gives back a Clarks shoe size with a width fitting letter, such as 3.5 F. The length scale on the gauge runs from 97 to 281 and the width scale runs from 67 to 227. Those numbers are not millimetres, so a normal size chart can't read them. This calculator can.
Around the calculator sit the tools a parent reaches for next: the Clarks size chart for UK, EU and US sizes, a cm and mm converter, a home measuring guide, an other brands converter and a set of fitting guides.
How it became essential
Shoe shopping for children moved online, and the fitting stool didn't come with it. A family that used to have a child's feet measured in store now often measures at a kitchen table, with a paper Clarks Foot Gauge and a child who won't stand still. The gauge does its part well. The gap is the step after it: two numbers on a strip of card, and no clear way to turn them into a size.
That gap is where wrong orders start. A guess between 2 sizes, a missed width letter or a misread scale means a parcel goes back, a week passes and the child keeps wearing shoes that pinch. Feet under 3 years old grow fast, so a family can go through that cycle several times a year.
Clarks Size Calculator closes that gap in one step. Parents type the 2 numbers, press one button and get the size and the width fitting together. Grandparents buying a gift use it with numbers sent by text. Parents abroad use it in their own language, because the page comes in 18. Over time the calculator stopped being a nice extra and became the step families do between measuring and ordering.
How results are worked out
The calculator looks up each length and width pair in a table of Clarks foot gauge results. The table is built into the page, so a result shows the moment you press Calculate size, with no wait and no download. When a pair is outside the table, the calculator estimates from the UK children's sizing scale and labels the result "Estimated result". When a length and width can't belong to a real foot, it says "No size found" instead of guessing.
Treat every result as a guide. Shoes differ by style, so check the fit at home or book a fitting appointment with a trained fitter.
Who looks after it
A small independent team builds and checks the site. Every change to the calculator is tested against the full gauge table before it goes live. The site works without an account, sets no tracking cookies and never asks for a child's name or age.
Independent and free
Clarks Size Calculator is an independent website. It is not affiliated with, endorsed by or connected to C&J Clark International Ltd, and "Clarks" is a trademark of its owner. We don't sell shoes and we don't take payment from shoe brands for results.
Get in touch
Spotted a result that looks wrong, or have an idea for the calculator? Tell us the 2 numbers you entered and what you expected on the contact page.